A/s Hoyer-ellefsen

Ingenior F. Selmer A/s

Norwegian Contractors

Ing. F. Selmer A/s

Ingenior Thor Furuholmen A/s

A/s Hoyer-ellefsen, Ing. T. Furuholmen A/s

Ing. T. Furuholmen A/s

Olav Olsen

Tomas Berge Einstabland

Jon Hermstad

Harald Bech

Arvid Slatten

An offshore platform structure of reinforced concrete for standing on the bottom of a sea as a consequence of its own weight. The structure includes a base supporting a tower for a platform deck. The lower part of the tower includes a cylindrical portion extending downwardly towards and through the base and providing a skirt. A frusto-conical annular wall extends coaxially with the tower between the tower and the top of the base to provide an annular chamber with a triangular cross section. Also a method of building a platform structure includes building the lower portion of the structure in a dry dock and floating the lower portion out into deeper water for continuing a casting operation for the remainder of the platform structure.

Offshore platform structure of reinforced concrete and a method of

Method for founding and stabilizing an off-shore platform which at its lower end is provided with skirts. The skirt or skirts are forced so deep down in the ground that a significant portion of the foundation area is transferred down to a depth where the load carrying strength of the ground is sufficient in regards to geotechnical stability and that it prevents an acceptable settlement. The platform (1) which is intended to be installed at very great depths, includes a foundation structure to be forced down in the sea bed, a cell portion that in its operational position is completely submerged, and an upper portion extending from the cell portion and up above the sea surface, where the submerged cell portion includes a centrally located cell surrounded by at least one cell portion.

Off-shore platform structure

Floating platform structure comprising a deck section and a support section supporting the deck section. The floating structure is manufactured in the shape of a trussed girder having an upper chord and a lower chord which are connected with one another by girder members and having a vertical cross section substantially in the shape of a triangle having an apex pointing downwardly, the deck section of the platform structure being provided by the upper chords of the girder. The buoyancy means of the platform structure are found in the upper portions of the girder members and the ballast means in the lower portions of the girder members and optionally in the lower girder chord. The support section comprises groups of at least three girder members each, said members converging from the deck downwardly towards a common point and being fixedly connected with one another in a junction point in or adjacent the convergency point. In an advantageous embodiment of the invention each group of girder members comprises four members presenting an upside down orientated pyramid, and two of the girder members in each pyramid meet two corresponding girder members of an adjacent girder member pyramid or group at the deck section.

Floating platform structure

A method for constructing an offshore platform structure having a plurality of supporting legs inclined inwardly towards each other is disclosed. The entire structure may be constructed in a dry dock, or optionally the lower raft may be constructed in the dry dock and then towed out to a deep water site where the structure is completed. The platform foundation includes a plurality of foundation footings and the lower end of the inclined supporting legs are built in the dry dock. The legs are cast in vertical position using conventional slip forms. Subsequent to the termination of the casting of the inclined legs the supporting legs are tilted towards each other and permanently interconnected at their upper ends. At their lower ends the legs are permanently anchored to the foundation footings. Remaining sections of the legs, if any, may then be cast in any conventional manner, preferably using slip forming.

Method for constructing an offshore platform structure having a

Marine structure having a base and a foundation means projecting downwardly from the base for pressing into the sea bed. The foundation comprises a wall system with pile means on both sides of the wall(s).

Marine structure

A multi-purpose marine structure intended to be submerged and installed on a sea bed. The structure comprises an outer peripheral body and a tapered inner section. The outer peripheral body is intended to be founded on a sea bed and comprises a tubular ring-formed body of concrete, the base of which is constructed and arranged to rest on a sea bed along its entire base periphery. The inner section is also of concrete and is formed as a cone or polyhedron having a lower end which is fixed to the outer peripheral body, the inner section tapering upwardly and inwardly from its lower end. The inner section and outer body together form a monolithic integral concrete unit, the inner section being fixed to the outer body along the inner periphery of the outer body.

Growing community of inventors

Oslo, Norway

Olav Olsen